"Charles Ferguson has informed us that he is not moving forward with his documentary about Hillary Clinton," CNN Worldwide spokesperson Allison Gollust told POLITICO. "Charles is an Academy Award-winning director who CNN Films was excited to be working with, but we understand and respect his decision."

"[W]e won't seek other partners and are not proceeding with the film," she wrote.

In a blog post on The Huffington Post, Ferguson said that pressure from Clinton aides and supporters, as well as the Republican National Committee, cast a chilling effect on potential sources and interview subjects.

"When I approached people for interviews, I discovered that nobody, and I mean nobody, was interested in helping me make this film," Ferguson wrote. "Not Democrats, not Republicans — and certainly nobody who works with the Clintons, wants access to the Clintons, or dreams of a position in a Hillary Clinton administration. Not even journalists who want access, which can easily be taken away."

Ferguson explains that after signing his contract with CNN Films, he began receiving pressure from Clinton press secretary Nick Merrill and Clinton aide Philippe Reines, "who contacted various people at CNN, interrogated them and expressed concern about alleged conflicts of interest generated because my film was a for-profit endeavor."

"After approaching well over a hundred people, only two persons who had ever dealt with Mrs. Clinton would agree to an on-camera interview, and I suspected that even they would back out," he wrote.

"This, of course, was the real consequence, and probably the real intent, of the announcements by the RNC, Philippe Reines, and David Brock," he wrote. "Neither political party wanted the film made. After painful reflection, I decided that I couldn't make a film of which I would be proud. And so I'm canceling. (Not because of any pressure from CNN — quite the contrary.)"

Ferguson called his decision to cancel "a victory for the Clintons, and for the money machines that both political parties have now become."

Merrill did not immediately respond to a request for comment; Reines declined to comment.

"But I don't think that it's a victory for the media, or for the American people," Ferguson continued. "I still believe that Mrs. Clinton has many virtues including great intelligence, fortitude, and a deep commitment to bettering the lives of women and children worldwide. But this is not her finest hour."